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Wednesday, June 5, 2019

Lawn Bowl Bias: On the Green and on the Test Table

Introduction

There was a prelapsarian time when all lawn bowls had about the same draw and furthermore, the rules of lawn bowls prescribed a minimum curvature that all legal woods should have. Whether for better or for worse this is no longer the case. Today, you can purchase traditional uniform sole wider swinging bowls or dual sole, narrow running bowls. The purpose of this blog is to better understand these issues concerning bowl bias.


The Present-Day Single Bias Test

There is at present only one test that a set of lawn bowls must pass to be acceptable to the lawn bowls regulators of the world. Each bowl must have at least as much bias as a working reference bowl (WRB) when rolled, without wobble, under standardized conditions, on a flat hard-surfaced table. This was not always the case. Before 2002, all bowls also had to have at least the bias of the WRB on a grass green or they had to pass a second table test which featured an initial 7% cant (tilt) of the bowl which produced an initial wobble on the testing table. In an action whose motives and blame has been in dispute ever since, the manufacturer’s representatives and the bowling organizations’ representatives, either out of guile or ignorance, eliminated these second phases for bowl testing. 

Why Bowls Bend

It is not an agreed fact that bowl’s curve only because of extra weight on one side of the bowl. In the web article, THE ROMANCE OF BOWL MANUFACTURE the late J. P. MUNRO wrote “contrary to the belief of many bowlers-and particularly those of the younger generation-the bias of a bowl is not brought about by extra weight on one side of the bowl, but by the shape of the crown or running surface, which is slightly higher on the non-bias side.” 

Changed Regulation Changes Manufacturing

Returning to the historic evolution of bowling bias, the change in the regulatory test regime had an immediate engineering consequence. Because a set of bowls now only needed to have as much bias as the WRB when released without wobble on the flat, hard testing table, only the curve of a narrow central strip of the running surface, (A) in the Figure, needed to be controlled so that in combination with the overall asymmetric mass of the bowl it would pass the new single-stage test. The two curved strips on either side of this central running strip, (B)s in the Figure, could be varied since they would not make contact with the hard testing surface. Manufacturers recognized that certain combinations of curvature for these edge running surfaces would cause bowls to run narrower on grass than the WRB.  In the diagram below, what I am saying is that the strip B on the left and the strip B on the right need not be mirror images.




How a particular bowl’s curved running surface interacts with different types of rinks would come to depend on what width of the running surface came into contact with that particular rink. If the bowl is rolling, without wobble, on smooth hardwood or linoleum the contact is only a very narrow band in the center of A. If the rink is a carpet, perhaps a wider portion of A is touching. If the surface is grass, the width of bowl touching the rink depends upon the length of grass; but certainly the A and  both B sections of the bowl’s sole would make contact. If the two B surfaces, acting together, have been engineered to subtract bias, then the bowl will run narrower on  softer playing surfaces than it ever ran on the hardwood test table.

How Wobble Effects Realized Bias

There is however a separate factor that, for these engineered non-uniform arc bowls, changes the exhibited bias on the hardwood test table. If such bowls are tilted slightly when they are set rolling down the test table they will wobble from side to side, at least initially, and this will cause both the A and B surfaces to contact the table. When modern era, dual sole bowls are tested with wobbling they do not exhibit the required minimum bias of the WRB bowl. But there is no longer a part B wobble test. Such bowls now pass the modern ‘bias test’ but go down an average grass green more narrowly than the WRB would. Some players who were brought up with the standard regulations of the last century sometimes call these dual sole bowls “cheater” bowls but they are no such thing. They are different because the regulation that tests bowls has changed and that has allowed a wider range of bowl performance than before. The unhappiness is understandable but, from my perspective, we need to play the game as we now find it!

The Pros and Cons of ‘Narrow’ Bowls

Because there are plenty of bowlers who believe that the game is easier to play with very narrow running bowls, such bowls, once they were ruled legal, were soon manufactured. These "variable geometry arc" types go down a green that is faster than 14 seconds with narrower than stated bias. It can be argued that they play the weighted run through (running) shots better, because hitting the head is less weight sensitive. Proponents also say they enable straighter drives, particularly on fast greens and particularly when delivered with an intentional wobble.
These claimed advantages are not without commensurate costs. For example, variable sole bowls may play quite well in the morning, when the greens are fresh but poorly in the afternoon when more tracking marks have been laid down, because when unbalanced sole bowls cross these runs at an acute angle they are more likely to be pulled offline. Even throughout the day, greater drawing inconsistency can be observed; some deliveries may turn into the head while others stay out. This is due to the bias-subtraction, inherent to these models, being disturbed not just by recently created ruts, but by wobble, wind, or general unevenness in the rink. Because of the latter, these dual sole bowls play poorer where green maintenance is an issue. All of these generalizations are more consequential for greens running 14 seconds or more such as most New Zealand rinks outdoors and rinks made with carpet, outdoors and indoors, everywhere. 
In summary, it is fair to say that narrow bowls play best in the hands of an experienced bowler who can consistently deliver bowls without wobble and who plays indoors where there is no wind and where the surface is hard and perfectly flat.
The balanced sole bowl is comparatively more stable because its profile is simpler but it can't be made to take the very narrow line down even the faster rinks that some players seek. It still probably has advantages for new bowlers or in high winds or on rutted or otherwise uneven greens. 

Tuesday, May 21, 2019

Playing the Extra End to Break a Tied Lawn Bowls Game




Many of my readers will have watched the top lawn bowlers playing sets on Youtube. There, in a tie breaker without exception, players who win the toss give the mat away and choose to have the last bowl. At the highest level, this is the best strategy, because there is little skill variation at different jack lengths and with different mat positions on an indoor carpet. 

This is not the case outdoors, at the club level, and particularly with teams. This was poignantly illustrated in an in-club drawn triples match yesterday as we opened the bowling season in Canada. I had squeaked out a tie at the end of the regular ends. For the extra end, we flipped a coin to decide who would have the choice and my opposing skip won.

His team comprised an excellent second-year bowler, a steady and competent 7th year bowler, and himself. My team comprised a first year lead playing in his first game, a 7th year bowler who was trying out new bowls for the first time, and myself. During the previous ends my tyro lead had bowled remarkably well and was most particularly noticeable on short jacks. On full-length jacks, he was either short or in the ditch. My second was all over the place with her new bowls and on long jacks, she was frequently out of bounds and without exception short. 

My skip opposite’s lead was inconsistent, both short and long, while his vice was in the head and more often than not behind the jack, even on long ends. Yet, with his choice, he gave away the mat and retained the last bowl advantage. In a singles match against me this would have been a reasonable choice since he is one of the club’s top bowlers; but, we were playing triples!!

Choose based on Team Strengths

When I lost the toss I thought I was doomed. Surely he would take the mat, call for a full-length jack and watch my colleagues flounder. But, as an automatic reaction perhaps, thinking of his own strengths, he took the last bowl and gave away the mat.

Overwhelmed, I called for a jack just a few meters past the hog line (to avoid my beginner lead delivering it too short); got it, and was rewarded with lead bowls close and behind the jack. Then my vice, because the length was less challenging, managed reasonably with her new bowls. Now my opposition skip faced a challenging head when he came to the mat. When the dust settled, my team had the three closest bowls in a situation where we only needed to get the one shot to break the tie.

My opposing skip is no dummy. He had won the club mens’ singles championship two years before; but, he made a quick and instinctive decision that would have been right for him at singles but was blatantly wrong for his team.


It’s more fun to learn from others’ mistakes than from your own! Take heed. Always consider the competencies of your team.

Sunday, May 19, 2019

Revisiting the Running Shot for Taking Out an Opposing Bowl at Lawn Bowls







Sometimes I forget what I have already been taught; so, it is a good thing that I reread my own posts occasionally! While I was working on a blog about removing an opponent’s single shot bowl, I vaguely recollected that the ’running shot’  was somehow connected with this. I found my article and guess what? - I was improperly using  drive and yard-on shots, each of which employs a different technique.

Rather than just linking to my original blog article I am reproducing the section describing the running shot here. I have subsequently followed the instructions and can confirm that the method works!

Running Shot


 The running shot, it is generally agreed, is more accurate than the drive shot. It is only when many bowls must be dispersed that the extra energy of a drive shot is needed. The running shot is purposed for a precise excision of bowl(s) from the head while the drive is a grenade into the head! In common practice, the drive is often used when the running shot is a better choice. The delivery of the running shot begins with the delivery arm holding the bowl hanging vertical and the body bent from the waist to bring the bowl close to the ground. Some players use a little backswing for this shot but no backswing is preferred. In setting a target point, reduce the draw width by two thirds and use this new aim line to set a target on that new line next to the object to be displaced. All running shots are delivered with the same weight: ditch weight. Swing the bowl a time or two along the aim line. The shot is delivered by pushing off with the stationary foot and taking a big step forward close and parallel to the aim line pulling the bowl with your body movement and pushing the bowl along the aim line to the target with your arm muscles. The idea is that consistency in the length of step and in the application of muscular force through the arm and fingers will produce a reproducible weight that is at least ditch weight. The backswing is minimized because it is this swing than can most often throw your body off line and cause aiming inaccuracy.

Thursday, April 11, 2019

The Delivery at Lawn Bowls: Bowling to the Shoulder

Aim for the Shoulder

Playing lawn bowls, I have never understood one recommended method for choosing a stare point. Many instructions teach to aim for the ‘shoulder.’ The shoulder is the point on the bowl’s anticipated path where it starts to significantly bend in towards the jack.  This point is advised as being 2/3rds to 3/5ths of the distance between mat and jack. The reason I have been unable either to understand or benefit from this teaching is that, as I understand it, the bias is acting all the way down the rink (with effect inversely proportional to the speed) and so if one aims at this so defined 'shoulder' your delivery must go narrow.
Why this May be Taught

I now have a hypothesis for why this method is taught.
It has been said with good reason that bowling is 90% length control and only 10% line control, so if aiming at the shoulder only causes an error of ½ meter (1/4 of the half-width of the rink), this technique will still give the best overall result if it can improve your estimate of length by ½ meter. This only requires an improvement of [ ½/23]X100 which is just 2%. But why would this method of aiming improve length at all? I can hypothesize a potential reason. This method may take into account the jack length better.
If you take a stare point 5 meters out from the mat, as I do, then during the delivery motion one’s only knowledge of the jack position is in one’s immediate short-term memory. Similarly, if you stare at a point on the front bank you are also not looking at the jack. If you see the jack at all it is only at the periphery of your field of vision. In contrast, staring at the shoulder of your intended delivery does present a good proxy for the jack position. That is, its distance away is always the same fraction of the jack length. Consequently, during delivery, you are being fed a reminder of the correct jack length. So, according to this hypothesis, you might be more likely to deliver the proper length. 
I think that there is a price to pay for this method of aiming. In another blog, I explain that if one aims using a stare point about 5 meters in front of the mat, it is easy to determine whether a poor bowl was caused by (a) missing your stare point or (b) choosing an improper stare point. If you missed your stare point on the inside, this will explain finishing narrow; if you missed outside, it is the explanation for your finishing with a wide bowl. Consequently, there is insufficient reason to believe that your stare point is the problem. On the other hand, if you did successfully roll your bowl over your stare point; then, if you miss narrow or wide, the problem is with the position of your stare point. This determination is easier with a stare point 5 meters or less in front of you since it will be blatantly obvious whether the bowl rolled over that exact spot. If you are looking 2/3rds to 3/5ths the way down the rink to the jack, it is not so easy to determine the difference between just missing your line or having the wrong line. 

P.S.

Whether you choose a stare point at the 5 meter length or at the shoulder has another consequence. The further down the rink your stare point is, the more erect your bowling stance needs to be to prevent neck strain, particularly if you wear corrective lenses.

P.P.S.

It is the "theoretical shoulder" that one should use as stare point. As explained in another blog, the "theoretical shoulder is the same distance down the rink as the actual shoulder but is on your aim line.   

Wednesday, March 27, 2019

Overcoming Rubbish Bowling



As I have been reporting, this winter’s bowling in Portugal’s Algarve region has been problematic to say the least. Today my wife and I had our last roll up at the Valverde LBC. We fly home on April 1st
The friendliness is terrific but what I have missed is the opportunity to get out on a rink alone and just practice deliveries one after another with a couple of sets of identical bowls. 
Today I played lead in a pairs game and just concentrated on delivering the jack with a consistent 45 degrees of backswing and smooth rhythm speed as I brought my body forward and particularly emphasized making sure that I walked off the front of the mat following the bowl a few steps as I released my bowl. This allowed me to swing through with a more relaxed arm. The extra elevation in the backswing provided extra velocity so that I didn’t have to give any final thrust at release. I could consequently hold the bowl more gently.

I left Valverde for another year with a more confident feeling.   

Saturday, March 2, 2019

An Unlawful Delivery at Lawn Bowls



At one of the places where I am visiting in Portugal, one of the bowlers uses, very effectively, a delivery technique which I had never seen before, at any level of lawn bowling, from the club level to the world championships; neither indoor nor outdoor. He starts standing, feet together, one stride behind the mat. Then, in one motion, he steps forward onto the mat, sets his foot on the mat and as he takes a second step forward with the normal advancing foot he releases his bowl. As he releases his bowl one of his feet is either fully or partially on or over the mat.

I was curious why I had never seen this done before. On further investigating I found the reason. Every such delivery is a foot fault! The pertinent law of the sport of bowls reads:

7.1          Before delivery a player must be standing on the mat with all or at least part of one foot on the mat.[my bold italics] At the moment they deliver the jack or a bowl, the player must have all or at least part of one foot on or above the mat.

Now what should I do? This gentleman has been bowling this way for years. I presume no one has ever called him for a foot fault all this time. He has probably never played in an officiated tournament. Should I speak to him about it off the green?
What would you do?  

Monday, February 18, 2019

When You & Your Opponent are Each Bowling Well from Opposing Hands


When you & your opponent are each bowling well but from opposing hands, the advantage is likely to pass from the side that is forced to switch hands because that side will have to judge afresh both the correct grass and weight. You can force your opponent to change hands by delivering a short bowl that crosses the center line and comes to rest in the opponent’s draw. Your opponent will probably get worried about hitting this bowl and promoting it onto the jack and for this reason, may be induced to change hand. This strategy can be seen being practiced in the match between Harlow and Chok  


So in this situation shade, your draw shot towards being narrow. If it is short it can block your opponent’s line. If it is perfectly weighted it can possibly trail the jack and if it is behind it becomes a good ‘catcher’ for your subsequent deliveries.


P.S. In the above-linked video Harlow also demonstrates a different tactic. When the draw on both sides is blocked he bowls with more weight for the bare jack and takes it and his bowl into the ditch. This occurs at time 1:16:23 on the video.

A Lawn Bowls Strategy for Playing Singles against a Perennial Skip





Suppose you most often play lead or vice in triples matches but now you are matched to play singles against a player who typically skips.  What possible advantage could you have? This was the question I asked myself recently here in Portugal when I was drawn against one of the top players in our men’s club singles tournament.

Leads and vices have more practice estimating the length of the jack seeing it just from the mat. Skips are the only players who regularly stand at the head and then later deliver their bowls. Consequently, they know precisely the distance from jack to mat when they walk to the mat end of the rink. They don’t have to guesstimate: they can even pace it off if they wish! This is different with singles play. Only the marker is in the head. The singles competitors must, each in turn, eyeball the jack and from that, work out their proper weight. 

That is, unless you as the opposition deliver standard lengths, placing the mat on the tee and sending full length jacks or some other length which an experienced bowler can handle in his sleep. Don’t do it…..every time you get hold of the mat move it up the green and deliver anything except a jack on the front tee. That way the ‘Perennial Skip’ is challenged to estimate the length from the mat alone and you quite possibly have more experience doing that. Furthermore, if you have delivered the jack, you have your muscle memory to help you. 

Rolling your ‘natural length’ from different mat positions is a strategy I have used.
This may not bring victory but it can avoid what otherwise might be a blowout!